I started writing this blog in 2006. Since then:
Robots have gotten better.
Sensors have gotten better.
Electric propulsion for planetary missions has become more capable.
Our ability to land a payload on Mars has increased a lot. In 2003 we landed a pair of 185 kg. rovers on Mars. The earlier Viking landers were heavier, but that included the dead weight of the landing stage on the surface. The Curiosity rover we landed in 2012 massed 899 kg. This took a lot of challenging, complicated engineering, but we made it work.
Our ability to support the ISS is more robust. In 2006, only two spacecraft were capable of carrying significant supplies to the ISS: Progress and the Space Shuttle. Currently, five can: Progress, Europe's' ATV, Japan's HTV, and the privately designed and built Cygnus and Dragon spacecraft from the U.S.
A privately developed launcher, SpaceX's Falcon 9, has made several successful flights, as well as one flight of an upgraded version. It doesn't have the payload capacity of the best western launchers developed under government contract, and it hasn't demonstrated equal reliability, but its pricing is attractive enough to draw a substantial launch manifest. If it can reliably launch at a tempo that satisfies demand it could lower launch costs. There's nothing like a spade-happy billionaire to push the envelope for space capabilities.
The worst development is the gap between the U.S. retiring the Shuttle and developing a replacement. NASA's hypersonic Ming vase was retired in 2011. Unfortunately, both NASA and Congress preferred to insist on launching the replacement Orion capsule on a new launcher designed to preserve as much as possible of the former Shuttle workforce, contractor spending, and NASA infrastructure and overhead.
The institutional incentives are as obvious as the results are lamentable. Instead of simply building a capsule and putting it on a version of the existing Delta IV with some spending to improve reliability, money that could have sped Orion capsule development has been wasted on other projects, first to pay for the aborted Ares I launcher and later for the Congressionally mandated SLS launcher, justifiably mocked as the Senate Launch System. Congressional underfunding of Commercial Crew Development is shameful.
On the brighter side, the U.S. still excels at missions beyond Earth orbit, and our Delta IV Heavy is the currently world's most capable launcher. And we have a laser-equiped robot on Mars!
But other nations have developed their own areas of excellence: Russia for flow-cost reliable launchers, Italy for habitable modules, and Canada for robotic arms. Here's to specialization and the benefits of trade!